Yes, you can easily create a package that can only be used on sessions between specific dates or terms by using our package tag system. You would give this new package it's own unique tag (for example Tag 10) and make sure that all sessions that you want this package to be used on within these specific dates also have this matching unique tag (Tag 10).
If you have existing evergreen packages on sale that you'd still like your customers to be able to use when booking onto sessions within these specific dates, then you'd just need to add this unique tag (Tag 10) to this package(s) as well.
Remember, a session can only ever have one tag, whereas a package can have multiple.
With this set up, as long as this new package has a long enough validity period, then your customers are able to purchase this new package/offer ahead of time whilst still allowing you to control the date it can be used up until.
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